-er eee eef eek eel eer eet ef- efe eff efl efr eft eke ekf ekl ekr ekt ele elf elk ell elr elt ere erf erk erl err ert ete etf etk etl etr ett fee fef fek fel fer fet ffe fff ffk ffl ffr fft fkf fkk fkl fkt fle flf fll flr flt fre frf frk frl frr frt fte ftf ftk ftl ftr ftt k-t ke- kee kef kek kel ker ket kff kke kkk kkl kkr kkt kl- klf klr klt krf krk krl krr krt kte ktf ktk ktl ktr ktt lee lef lek lel ler let lfe lff lfk lfl lfr lft lkl lkr lkt lle llf llk lll llr llt lrf lrk lrr lrt lte ltf ltk ltl ltr ltt re- ree ref rek rel rer ret rfe rff rfk rfl rfr rft rke rkf rkk rkt rle rlf rll rlr rlt rrf rrk rrl rrr rrt rte rtf rtk rtl rtr rtt te- tee tef tek tel ter tet tfe tff tfk tfl tfr tft tke tkk tkl tkr tkt tle tlf tlk tll tlr tlt tre trf trk trl trr trt tte ttf ttk ttl ttr ttt